The invention relates to a magnetic-tape-cassette apparatus comprising a head-mounting plate and a magnetic head arranged on the head-mounting plate and having a cylindrical tape-contact face and air gap, the magnetic head forming part of a head unit comprising a head support which, viewed in the direction of tape transport, comprises a tape guide situated before and after the magnetic head and having cylindrically curved guide surfaces bounded at one side by alignment surfaces at each time one of its axial ends, an imaginary surface connecting the alignment surfaces extending perpendicularly to a plane through the air gap, a control edge adjoining each of the guide surfaces at the other axial end and being inclined relative to the guide surfaces to urge the magnetic tape with one end against the relevant alignment surface during tape transport, and the axial length of the guide surfaces being smaller than or equal to the tape width.
Such a magnetic-tape-cassette apparatus comprising a head unit and a support forming part of the head unit is known from EP-PS 0,120,518 . The advantage of the head support in this magnetic-tape-cassette apparatus is that the magnetic tape is always in the correct azimuth position during its transport over the tape-contact face. This is important when prerecorded tapes are used, which have been recorded on other apparatuses. For a correct reproduction the azimuth position of the magnetic-tape-cassette apparatus should correspond to the azimuth position of the recording apparatus. Moreover, the manufacturer of the magnetic head can manufacture the head together with the support as a complete unit. The manufacturer of the apparatus then need no longer carry out any azimuth adjustments.
When the tape is thus guided the tape runs from one tape-guide surface directly before the magnetic head past the type-contact face of the magnetic head towards the tape-guide surface directly after the head. The tape in this tape path is slightly curved and is tautened. This stiffens the tape, so that the control edges can perform their control function in that they urge the magnetic tape in one direction against the alignment surfaces. In the Cue or MSS (Music Sensing System) mode, which is used for pause detection, the magnetic head is withdrawn. The tape is then no longer urged against the alignment surfaces.
From US-PS 4,646,186 it is known to arrange a pair forks, which serve to provide tape guidance in the play mode and whose tooth spacing corresponds substantially to the tape width, in the proximity of the magnetic head and to arrange a tape-guide fork having a larger tooth spacing and intended for the Cue mode further away from the magnetic head. When the magnetic head is withdrawn only the last-mentioned tape-guide fork is active. The tape guidance at the head will then be lost. At higher tape speeds this may give rise to oscillations, which may impair the reproduction of the signals from the audio track or even result in damage to the tape edges.